Priscilla Barrow, who has taught music in D.C. public schools for 22 years, learned Monday, out of the blue, that she will be going to the final performance of “Turandot” at the Washington National Opera on June 4 and, the next night, the company’s annual Opera Ball at the German Embassy. In a ball gown provided by the opera’s costume shop.

And that was a prize for a Twitter contest she didn’t even enter — given to her by winner Stephen Llewellyn, a British-born former barrister who now lives in Portland, Ore., whom she has never met.